What can cause penile pain and small bumps on the shaft. Std testing has come back negative and 4 doctors have said bumps are not STD related?

Biopsy. A biopsy of the bumps is indicated in light of the pain. The pain needs to be evaluated by a urologist to determine if there is underlying problem with prostate or uretha. If pain is burning senasation could be referred pain or urethritis with negative test.
PPP. Since std eval (-), likely are pearly penile papules, which are harmless. See: http://pppremoval. Hubpages. Com/hub/pearly-penile-papules-ppp-removal-treatments -- for more information and options on treatment, if desired. Consider condom use in general but also if concerned about bumps.